Portable rotary reversible tool



Feb. 25, 1941. L, FOSNOT 2,233,163

YORTABLLE ROTARY REVERSIBLE TOOL Filed Deo. 4, 1959 i jg wezjotg. I

ATTORNEY.

Patented Feb. 2s, 1941 PATENT OFFICE PORTABLE ROTARY REVERSIBLE TOOL Louis P. Fosnot, Aurora, lili., assignor to Independent Pneumatic Tool Co., Chicago, Ill., a corpo..

ration of Delaware Application December 4, i939, Serial No. 307,435

13 Claims.

rihis invention relates to pneumatically actuated reversible rotary portable hand tools adapted A for tapping, Teaming, drilling, screw driving and other kindred operations and having a pistol grip 5 handle at the rear end of lthe tool for the operator to hold and manipulate the tool in one hand by said handle.

The main purpose and object of my invention is to provide such Ia tool with a pair of easily operable control valves of the push button type for controlling the operation of the tool motor in opposite directions, said valves being mounted in the tool handle and operable at the upper end thereof by the thumb of the operators hand holding and grasping the tool by said handle.

A further object of my invention is to locate said control valves relatively close together, and preferably in side by side relation, so that said valves may be selectively operated by the operator by merely shifting his thumb from one valve to the other withoutl loosening or changing the grip of his hand on the tool handle.

A furthea` object of my invention is to have these valves biased to closed positions by spring means included in the valve structures and movable into'open pitlons in an axial direction and thus allow for the operation of the valves by a depression of the operators thumb on the upper ends of the valves towards the Itool handle.

A further object of my invention is to incorporate a revoluble exhaust valve in the motor case for changing the rotative direction of the tool motor and have said exhaust valve common to and operable by the push button valves in the depressi-on thereof.

It is also an object of my invention to provide a novel valve structure in the tool handle for controlling the amount of pressure iluid admitted to the tool motor for controlling its speed of rotation as may be required in the use of the tool.

The invention also contemplates the provision of a novel latch device for holding the forward valve in open position, when it is desired to run the tool motor in a direction to drive a tool bit or other working element into the Work without requiring the operator to hold his thumb on the control valve to keep the tool motor running.

'I'he invention consists further in the features hereinafter described and claimed.

In .the accompanying drawing- Fig. 1 is a longitudinal sectional view, with parts in elevation, of a pneumatically operated reversible rotary .portable hand tool having a pis.- tol grip handle'and embodying the features of my 5,5 invention;

ing the tool at the grip handle I. suiiiciently forward of the handle I to cause the operators hand when holding the .tool to more or Fig. 2 is a vertical sectional view taken through the tool at the handle portion thereof on line 2 2 of Fig. l; ,i

Fig. 3 is a horizontal sectional View taken on line A3 3 of Fig. 1; 5 Fig. 4 is a vertical sectional view taken on line -d of Fig. l;

Fig. 5 is an elevational view showing a part of the latch mechanism to be hereinafter more fully described; ann 10 Fig. 6 is a top plan View, partly broken away and in section respectively, of the parts shown in Fig. 5.

In the tool shown in the drawing, I indicates the pistol grip handle at the rear end of the.15

tool, and 2 indicates the motor case of the tooland from which motor case the handle extends downwardly as shown. The handle I and the convenient grip and hand-hold for the operators 25 l,

hand when holding and using the tool.

'The motor'case .2 is provided on its undersurface with a relatively short downwardly extending lug ll which .provides a purchase for the outer end of the operators iirst, iinger when hold- 3 The lug 6 is less rmly grip it with the -rst nger at the lug the handle is engaged by the palm of the operators hand and the thumb is uppermost and free to reach over the upper end of .the handle to se- 40 lectively actuate the' two push button control valves 1, 8 with which the tool is provided in accordance with my invention.

In the tool shown, the motor case 2 contains a rotary motor comprising a. rotor 9 with radial 45 piston Iblades I0 and a surrounding rotor chamber II. This construction is depicted in Fig'. 4, wherein it will -be noted that the rotor is eccentrically mounted within the chamber I-I and has a one-point peripheral contact therewith as `in 50 structures of 'this character. 'I'his arrangement in conjunction with the piston blades divides the chamber II into two fluid pressure sections a, h on opposite sides of the motor axis. "Said y sections are respectively connected by ports I2, I3 55 in the surrounding wall of the chamber I I with fluidpressure passages I4, I'5 provided by the motor case 2 on rthe outer side of said chamber as detailed in Fig. 4. The passages I4, I5 are divided at their lower ends by a web wall i8 and a cooperatingbushing I1, both located Within the motor case 2 below the chamber i4.

It may be remarked at this pointl that the motor exhausts through either the passage i4 or the passage I5 in the operation of the tool depending upon the rotative direction of the motor.

The passage I4 is used to run the motor forwardly, while the passage I5is used to run the motorin the reverse direction. The motor is run for-4 wardly, that is, towards the right, when tapping or reaming, and in the reverse direction or.

towards the left when withdrawing Ithe ftap or reamer bit from the work.

I'he push button valves 1, 8 control the admission of motive iluid, such as compressed air, to the rotor chamber H and also control the selection of the passages I4 and I5 for fthe exhaust.

This is brought; about by having the valves 1, 8

lactuate an exhaust valve I8 located within the bushing I1. In the tool shown, the valve 1 is the forward valve," while the valve 8 is the reverse valve." Designations to this effect may be marked either on the Valves them selves or on the motor case adjacent to them.

The rotor chamber Ii is closed at its opposite ends by end plates i8, I9 which also provide sup- .ports for anti-friction bearings 2i), 20 for the opposite ends of the rotorshaft-ZE as shown in Fig. 1. The forward end of the rotor shaft is connected by a suitable planetary reduction gearing 22 with the driving -spindle 23 of the tool.

This construction is shown in Fig. 1, and it will be noted that the spindle 23 is equipped with a bore extends through the handle I of the tool,

that is, the upper portion c of the handle where it joins the motor case 2 and closes the rear end of the same. The bore 25 is closed at its rear en d by a plug 26 secured in placeby a screw 21. The front portion of this bore mounts a cylindric screen 28 located between the front end of the bushing l1 and a. closure plug 29 as shown. The tool case has an exhaust opening 30 below the 'screen as shown.

The bushing I1, which is fixed against rotation in the motor case, yserves to mount the exhaust valve I8.y The latter has a. hollow, cylindric portion 3l rotatably tted within the bushing and provided with two longitudinally extending slots 32, 32'. These slots may be of equal length and are circumferentially spaced about the portion 3l. The bushing I1 has corresponding slots 38, 33', one for each of the valve slots. The arrangement is such that by rotating the valve member 3 I, the slots referred to may be selectively brought toregi-ster. This is apparent from Fig. 4 which shows the bushing I 1 andthe valve slots 32, 33 in register to connect the passage I4with the bore of the valve cylinder 3l and hence with the exhaust port 38 through the screen 28. It will be noted from Fig. l, that the valve cylinder 3l opens at its forward end into said screen.

The other ports 32', 33' in the bushing I1 and the valve element 3l are out of register 'when l the parts are positioned as in Figs. 1 and 4, and

the passage i is cut-oil;- from the exhaust. The

section b of the rotor chamber II is now 'on thelow pressure or exhaust side of the tool motor, while' the section a of said rotorchamber is' on the high pressure or inlet side of said motor. The pressure duid for operating the rotor is now ber II through the passage. I5. When running is connected to the exhaust throughthe bushing Hand the pressure fluid for operating the rotor is supplied to the section b of the rotor chamber through the passage I 4 as will presently appear. The rear` end of the valve member 3| is closed to provide an en'd'surface 34 and a beveled suradmitted to the high pressure side of the chamthe rotor in a reverse direction, the chamber I5 facev 35, the latter to seat against the rear endA A of the'bushing I1. A stem 38 extends rearwardly from the Avalve member 3| in axial alinement therewith and is provided Vwith a radial projection 31 having milled surfaces 38, 39 on opposite sides of the valve axis. The handle I is provided with a. pair of uid pressure passages 40l below the supply hose nipple connection 45, the supply hose being shown at 46.

The drillings for the passages continue through the upper portion c of the vhandle I to the rear of the, motor case -and accommodate bushings 41, one foreach of the push Valves 1,

` 8. With the passages 40 in side by side relation,

the valves are similarly located to facilitate their selective depression to open positions by the thumb of the operators lhand grasping the handle I. vThis arrangement also positions the valves 1, 8 in line with the projection 31 for turning the same. The bushings 41 extend from the chamber si to the upper end of the handle I and seat against shoulders 48 therein as shown. l

The bushings are held in place and against rota.- tion by set screws (not shown), one for each bushing.

Each push button valve 1, 8 has a rod 45) slidably mounted within its vassocatedbushing 41. The rods 49 extend through the bushing and are provided at their lower ends with the valve members heretofore referred to.I These valve members seat against the .lower ends of the bushings 41, the valve members being marked 50 and 5I, respectively. The member 50 is on the rod 49 for the forward valve 1 and the member 5I is on the rod for the reversing valve 8. The valve members 50, 5I are within the chamber 4I below the bushings and are movable kinto and out of closing relation to beveled valve seats 52 at the lower ends of the bushings.

The valve members 50, 5I also act on the projection 31 to turn the exhaust valve I8 in op-A posite directions.

members 50, 5I are immediately above the pro.

For this purpose the valve jection on opposite sides of itsA rotative axis. Hence, on depressing the rod 49 of the forward valve 1, the valve member 50 will turn the exhaust valve i8 in one direction, while the valve member 5I on being depressed will turn the e'xhaust valve in the opposite direction. This occurs in alternation if the valves 1, 8 are operated in that manner. On the other hand, after the exhaust valve I8 has been turned by a push valve, the exhaust valve will remain in that position until'turned by the other push valve. This will be apparent from Fig. 2 which shows the exhaust valve I8 set for a forward rotation of the tool motor. The forward valve 1 may now be opened and closed as often as desired without changing the exhaust valve because the projection 31 is against the reversing valve member 5I. The valve members 50, 5I limit the rotary movement of the exhaust valve I8, and the under surfaces of said valves and the milled surfaces 38, '39 are. curved to facilitate the action of the parts.

It will be noted that the bushing I1 supports the exhaust valve I8 for rotative movement and also locates the end surface 34 in the chamber 4I. 'Ihis subjects the end surface 34 to the pressure fluid in said chamber and seats the exhaust valve against the bushing I1 to prevent leakage from the chamber 4I to the 'bushing I1.

The rods 49 of the pushvalves have sliding engagement within their bushings 41 above chambers 53, 53 which the bushings provide at their lower ends. These chambers have ports 54, 54 which connect with fluid pressure passages 55, 55' in the tool case between the bushings 41 and the adjacent end plate I9. Said pas sages connect with ports 56, 56 in said end plate and said ports register with ports 51, 51' in the adjacent end of the rotor chamber II at the passages I4, I5 as shown. The end plates I9 are iixed inthe motor case against rotation by dowl pins as illustrated herein.

When the valve member 50 is unseated pressure fluid enters the section a of the tool motor Y to rotate the rotor 9 forwardly. The path of the Y to the tool motor.

pressure fluid from the chamber 4I to the passage I5 is through the chamber 53 at the forward valve 1 and the connected ports and passages 54, 55, 56 and 51 as shown in Fig. 3. The exhaust valve I8 is now in position connecting the low pressure side b of the motor with the passage I4 as shown in Fig. 4'. When the valve member 5I is unseated the iiuid pressure is supplied to the section b of the tool motor and the rotor is run in the reverse direction. The path of the pressure fluid is now from the chamber 4I to the passage I4 through the chamber 53 at the reversing valve 8 and the connected ports and passages 54'., 55', 56 and 51' aswill be apparent from Fig. 3. At this time the exhaust valve I8 is connected to the motor section a.

It is to be understood that the valves 1, 8 must be held depressed to supply motive uid When a valve is released, its spring 58 raises the valve and cuts off the motive uid supply to the bushing which it serves. Each spring 58 is located adjacent the upper end of its valve 1 or 8, .the bushing 41 being enlarged at 59 to house and support the spring. The valve rods 49 carry cap elements 60, one on the upper end of each rod, to t' overitsspring 58. The

latter bears at its upper end against its cap and at its lower end against the bushing as shown in Fig'. 2. The caps 60 also provide enlarged heads on the upper ends of the valve rods to facilitate their depression by the operators thumb.

To lock the forward valve 1 in open position when `so desired, lI provide a latch element 62 on the side of the handle I at said valve as shown in Fig. 2.- This latch element is mounted on a pivot screw 63. A cover plate 64 is held by this screw over a recess 65 in which the latch element is located and said cover plate also retains in said recess a. spring member 66 which normally urges the latch to a releasing position out of en- A end bears against the opposite side of the latch.

The cap element 60 at theupper end of the valve 1 provides an annular channel 68 to receive the free end o f the latch 62 to hold the valve 1 depressed as shown in Fig. 6. The upward pressure of the valve spring 58 will hold the parts against accidental' release. The channel 68 is wide enough to provide for the automatic release of the latch on pressing the valve 1 downwardly.

To control the amount of motive fluid which may be supplied to the tool motor, I provide a regulating valve 69 in the tool handle I at its lower end, that is, in the depending grip portion as shown in Figs. 1 and 2. This valve comprises a bushing 10 fittingwithin a bore 1I in the tool handle. The bore 1I is a downward continuation of the chamber 42 and is intersected by the passage` 43 as shown. The bushing 10 has a surrounding exterior groove 12 at the passage 43 and a number of ports 13, 13 of different sizes connecting the groove with the bore 14 of the bushing, the latter opening into the chamber 42 as shown. To control these ports, the bushing mounts a valve rod 15 which by a turnable nut 16 on the screw threaded lower end 11 of the valve rod 15 adjusts said rod to open and close all or some of the ports 13 as will be apparent from Fig. 1.

The bushing 10 is seated in the bore 1I by a threaded sleeve 18 which carries a yoke shaped bracket 19 exposed below the handle I to accom- Y down by turning the nut 19 in the desired direction.

v- The handle I may be provided with a reservoir chamber 8| for holding a supply of oil for lubricating the operative parts of the tool. An oil lter and feeding device 82 controls the supply of oil to the stream of pressure fluid as it passes through the inlet chamber 42. The handle I is provided with a lling opening for the reservoir andan opening to insert and remove the filter.

It will be noted that the upper ends of the push button valves 1, 8 normally extend above the handle at the rear end of the tool and thus are positioned within convenient and easy reach of thethumb of the operators hand graspingand holding the tool at said handle. Moreover, with these valves opening with a downward movement they may be readily depressed by the thumb without disturbing or changing the grip of the operators hand about the handle. With the handle carrying a forward valve and a reversing valve, the tool motor may be run in the direction desired at the will of the operator.

Another important feature is the interaction between the control valves 1,- 8 and the exhaust valve I8. The latter is common to the push valves and hence said push valves may be located relatively close together for the thumb operation referred to.

'Ihe tool is relatively light in weight and is compact in design. Being of the pistol grip type, it may be held and operated in Vone hand and hence is adapted for drilling, tapping, `rea'n'iing and screw and nut driving operations as before stated in close and confined quarters.

. The control valve 69 is another important feature of my invention. 'I'his valve by its various sizes of ports I3 and its adjustable valve rod 'I5 enables the amount of pressure fluid ladmittedto the tool motor to be so regulated as tocontrol the speed of its rotation. This allows the motor speed .to be adjusted to the particular character of work to be performed by the tool. I claim as my invention: 1. In a pneumatically operated reversible rotary portable hand tool having a grip handle at the rear end of the tool, a reversible Amotor and a spindle driven thereby, aI pair of depressible push button valves mounted in the handle for controlling the supply of motive fluid to the tool motor for rotating the' same in opposite directions, means for biasing said valvesv to closed positions, and means providing operable portions for'the valves and available at the upper end of the handle whereby the valves may be selectively depressed into open positions by the thumb of the operators hand graspingl and holding the p tool by said handle.

2. In a pneumatically operated reversible rotaryportable hand tool having a grip handle at the rear end of the tool, a reversible motor and a spindle driven thereby, a pair of depressible pushbutton valves mounted in the handle for controlling the supply of motive iiuid to the tool motor for rotating the same in opposite directions, means for biasing said valves to closed positions, and means providing operable portions for the valves in side by side relation at the 'upper' end of the handle within the lateral connes of the tool whereby the valves may be selectively depressed into open positions by the thumb of the operators hand grasping and holding the tool by said handle,

3. In a pneumatically operated rotary portable hand tool having a motor case and a pistol grip handle secured theret at the rear end of the tool, said handle having its upper portion to the rear of the motor case and its lower end portion extending downwardly therefrom, a motor in said case, a spindle driven by said motor, a depressible push button valve mounted in the upper portion of the handle to the rear of the motor case in substantially normal relation to the longitudinal axis thereof for controlling the supply of motive iiuid to the tool motor for rotating the same, means for biasing said valve to closed position, and means providingan operable portion for the valve at the upper end of the handle whereby the valve may be depressed into open position by the thumb of the operators hand grasping `and` holding the tool by` said driven by said motor, a pair of depressible push.

button valves mounted in the handle for controlling the supply of motive fluid to the tool motor, means for biasing said valves to closed positions. means providing operable portions for said valves and available .at the upper end o1 IendA of the too1,la reversible motor in said case,

a spindle driven by said motor, a pair of depressible push button valves mounted in the handle for controlling the supply of motive i'luid to the tool motor, means for biasing said valves to closed positions, means providing operable portions for the valves and available at the upper end of the handle Wherebysaid valves may be selectively depressed into open positions by the thumb of the operators hand grasping and hold.-

ing the tool by4 said handle, and an exhaustfvalve rotatably mounted in the motor case and turnable in opposite directions by the push button valves for changing the rotative direction of the tool motor. v

6. In a pneumatically operated reversible rotary portable hand tool having a motor case and a grip handle secured to said case at thev rear end of the tool, a reversible motor in said case, a spindle `driven by said motor, a pair of push button valves mountedl in the handle for controlling the supply of motive fluid to the tool motor, means for biasing said valves to closed positions, means providing operable portions for th valves and available at the upper end of the handle whereby the `valves may be selectively depressed into open positions, and an exhaust valve for said motor, said exhaust valve being revolubly mounted in the motor case and having projections on opposite sides ofv its rotative axis for engagement by the push button-valves onv the depression thereof for changing the direction of rotation of the tool motor. I

'7. In a pneumatically operated reversible rotary portable hand tool having a motor case and a grip handle secured to the motor case at the rear end of the tool, a reversible motor in said case, a spindle driven by the motor, a p air of push button valves mounted in the handle for controlling the supply of motive fluidl to the motor, means for biasing the valves to closed positions, means providing operable portions for the valves at the upper end of the handle whereby the valves may be selectively depressed into open positions, and an exhaust valve for the motor, said exhaust valve being Arevolubly mounted in the motor case and having radial projections on opposite sides of its rotative axis for engagement by the push button valves in the depression thereof forchanging the rotative direction of the motor, said push button valves providing stops for limiting the rotative movement of the exhaust valve. y l

8. In a pneumatically operated reversible rotary portable hand tool having a motor 'case and a grip handle secured to said case at the rear end of the tool, a reversible motor in said case, a spindle driven by the motor, said handle having a passage-way therein for supplying lmotive fluid to the motor, an exhaust valve for the motor, said exhaust 'valv'e being revolubly mounted in the motor caseand having a radial; projection in said passage-Way, and a pair of depressible valve members mounted 'in' said pas-` sage-way for controlling the flow of motive uid therethrough and engageable with said proies# tion for turning the exhaust valve for changing the rotative direction of the tool motor. and rods i connected with said valve. members and slidably mounted in the handle for selectively opening the valve members and changing the position of the exhaust valve.

9. In apneumatically operated rotary portable hand tool having a grip handle at the rear end of the" tool,V a motor and a spindle driven thereby,

a depressiblepush button valve mounted in the handle for controlling the supply. or motive uid,

to the tool motor, means for biasing said valve to 'closedpositiom means providing an operable portion for'the valve at the upper end of the handle whereby the valve may be depressed into open position bythe thumb of the operators hand grasping and' holding the tool by said handle, and a latch device carried by the handle forreleasably holding said valve in open position.

.,10.'In a pneumaticallyoperated rotary portable hand tool having a grip handle at the rear end of the tool, a motor and a spindle driven ,I thereby, a; depressble push button valve mounted o mounted on the handle and movable into engageeva:

'ment with' said valve for holding the .same in openfposition, and spring means biasing the latch -to its release position.

"11". In a pneumatically operated reversible rot-ary portable hand tool having a grip handle atlfthe rear end of the tool, a reversible motor and a spindle driven thereby, said handle having a fluid pressure supply passage therein for the motor, an exhaust valve mounted in the motor case for the motor andohaving a radial projection iii said passage, depressible valve members in said passage and selectively operable against the projection for turning the exhauff.'J valve for changing the rotative direction of the motor, rods slidably mounted inthe handle and connected 'with theyalve members, and bushings in the handle for 'said rods, said bushings Droviding seats at their lower ends for the valve members.

12. In a pneumatically operated portable hand tool having a motor and a grip handle at the rear end of the tool. said handle having a passage-'way for supplying pressure fluid to the tool motor, and a valve device carried by the tool in said passage-way for regulating` the amount of pressure iluid admittable to the tool through said passage-way,- said valve device having'a bushing located in said passage-way and having a number of ports of different sizes, and a valve rod adjustably mounted in said bushing for opening and closing said ports.

13. In a pneumatically operated portable hand tool having a motor and a pistol grip handle at the rear end of the tool, said handle having a passage-way therein for supplying motive uid to the tool motor, a valve device in said passageway, said valve device having a bushing in said passage-way and provided with a number of axially disposed ports of diflerentsizes, a valve rod slidably mounted in said bushing for opening and closing said ports, and a turnable nut engaged with a-threaded portion of said rod for adjusting the yposition thereof with respect to.v

said ports. l

LOUIS P.FOSNOT. 

